Concepts · Terminology
File formats and core concepts · 16 answers
- How Do Java and Bedrock World Formats Differ? Java Edition stores worlds as region/.mca (NBT); Bedrock uses db/ (LevelDB). The formats aren't interchangeable. TopoBlocks diagnoses free on-device and offers one-way Java to…
- What Are Java's region/.mca Files? A plain-English look at region/r.x.z.mca files in Java Edition worlds: they store chunks by region in NBT binary, unlike Bedrock's db/ (LevelDB). TopoBlocks diagnoses them…
- Behavior Packs vs Resource Packs: What's the Difference? Bedrock behavior packs (change game logic/entity behavior) vs resource packs (change looks/sounds), why they're stored apart from world files, and how TopoBlocks handles Java…
- What Is a Minecraft Chunk? A chunk is a 16×16 world unit, and world data is stored and loaded per chunk. Learn what chunks are, how TopoBlocks validates world structure on-device for free, and why…
- How Are the Overworld, Nether & End Stored in a World File? All three dimensions live in one save: Java uses folders like region/, Bedrock uses db/. TopoBlocks diagnoses each dimension free, on-device, never overwriting your file.
- Where Are Game Mode, Difficulty & Game Rules Stored? Game mode, difficulty, and game rules are world-level settings stored in level.dat (NBT format). TopoBlocks can read this metadata locally for free, with no upload by default.
- What is the difference between level.dat and level.dat_old? level.dat_old is the previous automatic backup of level.dat — a fallback clue when level.dat is corrupted, but not a full world backup. TopoBlocks can diagnose level.dat…
- What Format Is NBT? Why Won't level.dat Open? NBT (Named Binary Tag) is Minecraft's binary tag format for world metadata, entities, and block entities; level.dat is NBT. TopoBlocks reads these structures on-device, never…
- What Is a Minecraft Seed and What Does It Affect? A plain-English guide to Minecraft seeds: the random number that drives vanilla terrain generation, stored in level.dat. Plus why real-map worlds from TopoBlocks are a different…
- World (.mcworld) vs Template (.mctemplate): What's the Difference? .mcworld is one specific world; .mctemplate is a template you use to create new worlds, spawning a separate copy each time. TopoBlocks diagnoses and repairs these renamed ZIPs…
- What Is the level.dat File? And Why It Matters level.dat is the metadata file inside a Minecraft world save. It stores the name, game mode, seed, spawn point, and game rules. It must sit in the world's root folder; if it's…
- What Is the db Folder (LevelDB) in Bedrock? The db folder in a Bedrock world is a LevelDB database that stores the actual world data—chunks, blocks, entities, and more. It plays a different role than level.dat, and if it…
- What are .mcpack / .mcaddon / .mctemplate files? .mcpack is a single resource/behavior pack, .mcaddon bundles multiple packs, and .mctemplate is a world template — none of them are a complete world, which is what sets them…
- What is a .mcworld file? How do you open it? .mcworld is a world import file for Minecraft Bedrock — essentially a ZIP archive with a changed extension. Open it on any device that has Bedrock installed to import the entire…
- What is TopoBlocks? TopoBlocks is an independent iOS tool for .mcworld files, real-map Minecraft worlds, Java-to-Bedrock conversion, backups, and server hosting.
- Where Are Minecraft Saves? Understanding the World File Structure A Minecraft world save is made up of level.dat, db/ (LevelDB), levelname.txt, and more; the location differs by platform. On iOS it lives inside the app sandbox, so you must…
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